Compressor

ABSTRACT

A FOUR CYLINDER COMPRESSOR HAS ITS CYLINDERS RADIALLY SPACED 90* AROUND A CRANKSHAFT AND ARRANGED AS TWO PAIRS OF COAXIAL OPPOSED CYLINDERS, THE TWO PAIRS BEING SLIGHTLY OFFSET ALONG THE AXIS OF THE SHAFT, THE TWO CYLINDERS OF EACH PAIR HAVING INDIVIDUAL PISTONS RIGIDLY CONNECTED BY MEANS INCLUDING A TRANSVERSE YOKE DRIVABLE BY THE CRANKSHAFT THROUGH AN INTERPOSED SLIDE. THE DIECAST CYLINDER BODY HAS A NECKED CLOSURE AT ONE END WHICH SUPPORTS INTERNALLY THE DRIVESHAFT SEAL AND FRONT CRANKSHAFT BEARING AND CARRIES EXTERNALLY THE DRIVE PULLEY BEARING AND MAGNETIC CLUTCH. AT ITS OTHER AXIAL END A SEALED AND CHAMBERED CLOSURE ASSEMBLY DEFINES THE DISCHARGE PLENUM AND OIL SUMP AND CARRIES THE REAR BEARING WHICH JOURNALS A DISC WHICH DEFINES THE REAR THROW OF THE CRANKSHAFT. INDIVIDUAL HEADS AND DISCHARGE VALVE PLATES ARE ON THE CYLINDERS. INTAKE VALVES ARE IN THE PISTONS. LUBRICATION IS THROUGH A CAPILLARY TUBE FROM A HIGH PRESSURE OIL SUMP IN THE DISCHARGE PLENUM VIA A LOW PRESSURE OIL CHAMBER BEHIND THE CRANKSHAFT.

Unit States Patent 11113 5206 [72} Inventors Edwin L. Gannaway 3,21 1,365 10/l965 Phelps 230/206 y; 2,044,269 6/1936 Williams. 184/6 Robert M. Draper, Sidney, Ohio 2,128,065 8/1938 Aikman 184/6 1211 PP 7471920 FOREIGN PATENTS [22] FM 261968 556,318 7/1923 France 230/185 [45 1 meme! 507 050 4/1927 0 rm 103/174 [73] Assignee Copeland Refrigeration Corporation, 8 any Sidney, Ohio Primary Examiner-William L. Freeh Artarney- Harness, Dickey and Pierce [54] COMPRESSOR 5 Claims, 6 Drawing Figs.

184/6- 417/437 92/153 ABSTRACT: A four cylinder compressor has its cylinders [51] int. Cl F011) l/02, radially Spaced 90 around a crankshaft d arranged as two Fmb 31/10 pairs of coaxial opposed cylinders, the two pairs being slightly [50] Field of Search 230/187, ff t akmg the axis f the shaft the two cylinders f each pair 206, 194; 103/185, 174; 134/6; 17/ 92/74 having individual pistons rigidly connected by means includin a transverse oke drivable by the crankshaft through an in- [56] References Cned tefposed slide. T 11e diecast cylinder body has a necked closure UNITED STATES PATENTS at one end which supports internally the driveshaft seal and 1,558,620 10/1925 Kagi 230/207 front crankshaft bearing and carries externally the drive pulley 2,504,528 4/1950 Hume 230/206 bearing and magnetic clutch. At its other axial end a sealed 3,238,890 3/1966 Sadler et al.. 103/171 and chambered closure assembly defines the discharge 3,340,818 9/1967 Schanzlin 103/216 plenum and oil sump and carries the rear bearing which jour 1,565,640 12/1925 Green... 230/187 nals a disc which defines the rear throw of the crankshaft. 1nl,320,833 /1931 Hueber. 230/187 dividual heads and discharge valve plates are on the cylinders. 2,147,666 2/1939 Park 230/187 Intake valves are in the pistons. Lubrication is through a capil- 2,513,547 7/1950 Buell 230/206 lary tube from a high pressure oil sump in the discharge 2,529,996 11/1950 Browne 103/1 74X1 plenum via a low pressure 011 chamber behind the crankshaft.

j/ Z/ Z7 7 7f 7] PATENTEU JUN28 |97l 3; 5871406 sum 2 OF 5 EJEH INVENTOR'.

COMPRESSOR BACKGROUND OF THE INVENTION The present invention relates to an improved compact, high-efficiency refrigeration compressor especially adapted for use in automotive air-conditioning systems. Important objects of the invention include the provision of such compressor which can be mounted in various positions so that the unit is adaptable to different vehicle installations, and the provision of a unit which is very compact in proportion to its output, inexpensive to construct,.extremely rugged and reliable, and relatively free from noise vibration and equipped with improved lubricating means.

Other objects and advantages will become apparent upon consideration of the present disclosure in its entirety.

DESCRIPTION OF THE FIGURES OF DRAWING FIG. 1 is a central longitudinal sectional elevational view of a compressor constructed in accordance with the present invention;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear elevational view with the rear cap and end cover removed;

FIG. 4 is a view similar to FIG. I showing another embodiment of the invention;

FIG. 5 is a rear elevational view with the rear closure removed; and

FIG. 6 is a front view.

DETAILED DESCRIPTION OF PREFERRED FORMS OF THE INVENTION Certain features of the lubricating means discussed herein are also disclosed in our copending application Ser. No. 767,030, filed Sept. 9,1968, as a continuation of application Ser. No. 7l3,58l,filed Mar. I8, 1968.

Referring now to the drawing, reference character 10 designates generally the diecast body of the compressor. The body is provided with two pairs of opposed axially aligned cylinders arranged upon axes which are perpendicular to each other and to the axis of the crankshaft 20 and comprising, with the compressor in the position shown, top and bottom cylinders 11, 12 aligned on a vertical axis and transverse cylinders 13, 14 aligned on a horizontal axis. The transverse cylinders are offset forwardly from the vertical cylinders sufficiently so that the driving yokes 25, 26 for the two pairs of cylinders may be positioned side-by-side on the same throw 21 of the crankshaft. The compressor body has an integral front wall which supports a main front crankshaft bearing 16. The rear end of the crankshaft is formed by an initially separate cylindrical portion 22 fixed to the throw and journaled in a concentric reentrant bearing wall 31 formed as an integral extension of the compressor rear closure 30. Closure 30 is accurately fitted in a large bore 32 in a rear wall portion 35 which is in tegral with the body casting, and is retained therein by a snap ring 36.

The crankshaft extends forwardly through bearing 16 and through a front extension member 39 which forms a rigid extension of the front wall 15 and contains an inlet manifold chamber 43 within an enlarged rear portion 41 thereof and which is secured by capscrews 42 to the front wall 15. Suction gas is delivered to inlet manifold chamber 43 via inlet fitting 44 and is conducted from chamber 43 into the interior of the compressor through port 45 in front wall 15. The interior section 41 defines a seal chamber 46 containing a conventional shaft seal assembly 47.

A neck portion 40 integral with chambered section 41 extends forwardly around the shaft and carries pulley bearing 52. Secured on the projecting end of the shaft is the driven element 48 of a magnetic clutch assembly generally designated 50, the details of which do not form a part of the present invention. Pulley 51 is journaled on the antifriction bearing assembly 55 and is contoured to extend freely around the annular solenoid or coil 52 of the magnetic clutch. Coil 52 is supported by a web 53 from member 40, 41. Energization of the coil 52 pulls the armature 54 against and couples it to the web 53 of the pulley to drive the compressor, as will be understood.

Each piston comprises a diecast body portion which is axially short, fitted with a sealing ring 61 and has an integral inwardly extending neck 62 attached by a screw 63 to a boss 64 on yoke 25, as shown in section in cylinder 11 in FIG. 1. A slide block 65 in the yoke is rotatably fitted on crank throw 21. The symmetrically opposite boss portion 66 of the yoke 25 is connected in like fashion to the opposed piston in the cylinder 12. The yoke 26 for the horizontal pistons is similarly actuated from the crank throw 21 via slide block 67. A counterbalance 70 on the crankshaft offsets the inertial forces.

Suction gas enters the inner ends of the cylinders, .&all of which open into the annular space 72 defined by the housing at the forward end thereof. The pistons are provided with inlet ports 74, an inlet reed valve 75 for all of its ports being carried by each piston, to which it is secured by the screw 63. Outward movement of the piston forces the gas past valve plate 77 and outlet valves 78 into head chamber 80 from which the gas flows to the rear of the compressor via passages 82 and 83 in the body casting and rear wall 30 respectively, and into the discharge plenum chamber 84 defined by rear end cap 85 which is secured by the central cap screw 86 to rear wall 30. The passage 83 is located at a position which will be above the oil level in chamber 84 in whichever position the compressor is mounted. Any oil which travels through the system is swept out of the cylinders by the velocity of the gas, but the velocity drops as the gas enters the relatively llarge chamber 84, so that the oil tends to separate, fall out and remain in the bottom of chamber 84. Discharge gas is taken from an upper portion of chamber 84 via outlet fitting 88.

Oil for lubrication of the compressor is taken from the bottom of chamber 84 via screen 90 and capillary tube 91, which meters the flow of lubricant. Capillary tube 91 delivers the oil into an annular chamber 92 formed in the inner surface ofwall 30 and facing the interior of the crankcase area of the compressor but substantially closed by the rotating crankshaft rear disc portion 22. An oil hole 95 in crank throw 21 is open at its left end into and orbits in communication with chamber 92 and communicates with other passages 96, 97 leading to bearing 16 and seal chamber 46 for lubrication to these parts. The seal chamber is vented back to the crankcase by vent passage 98.

If it is desired to mount the compressor in a different position, for example, with cylinders 13-14 vertical and cylinders 1112 horizontal, the end cap 85 may be turned 90", and the capillary tube may be bent sufficiently, due to the fact that it has several convolutions, so as to place the inlet screen 90 at the bottom with the compressor in its intended mounting position, the discharge fitting being moved to a high point by the turning of the plenum cap 85. The front extension member 39 may also be turned to and reinstalled in different positions de pending upon the intended mounting of the compressor.

In the embodiment of the invention shown in FIG. 4, the overall length of the compressor is substantially shortened. The inlet and outlet fittings 144188 respectively are mounted directly on one of the heads 181. A separate member 139 defines the front wall portion and neck portion 140 is integral therewith, member 139 being secured to the open front of the body by a series of capscrews 142. The magnetic clutch solenoid and pulley 151 are similarly carried on the front wall portion and neck respectively, but the drive flange 148, which carries the armature 154 by means of flat leaf springs in a well-known manner, is secured to the shaft 120 by axially adjustable means. The shaft has parallel flats 220 on opposite sides at its forward end and is divided into two sections by a diametric slot 221 parallel to the flats. Prior to slotting, the end of the shaft is axially drilled and tapped with a tapered pipe thread, and a tapered screw plug 222 is inserted to act as a wedge. When the plug is tightened, the sections on opposite sides of the flat are spread to tightly grip and position flange 148, the axial hole in which conforms to the size and shape of, and has a slip fit on, the flatted undistorted shaft. Other components of this embodiment are designated by reference numerals corresponding to those used in connection with similar components of the first embodiment but 100 integers higher, and detailed redescription of many of the parts will not be required.

In the first embodiment the main components are assembled into the compressor from the rear, while in the second embodiment they are installed from the front. In both embodiments, however, the seal is accessible from the front. The journaled rear portion 122 of the crankshaft in the second embodiment also includes a counterweight portion 171. The yokes are installed on the crank throw before the journaled rear portion of the shaft is attached, the journaled portion 22 or 122 is then attached, the shaft and yokes are positioned in the compressor body, and the pistons are installed and attached through their respective cylinders.

The head chambers of the bottom and horizontal cylinders of the second embodiment are connected to the discharge plenum chamber 184 above the oil level by passages 201, 202, 203 cored in the body and discharging into a central circular chamber 204 formed partly in the body and partly in rear closure 185. Chamber 204 is isolated from plenum 184 by mating annular wall portions 205, 206, 207 except for communication via an opening 210 at the top. A reentrant discharge tube 212 extends from outlet fitting 188 into passages 182, 183 to shield the outlet from entrained oil.

Although it will be seen that alteration of the second embodiment after manufacture to permit its installation in different positions is not as readily effected as in the case of the first embodiment, the symmetry of this d-esign is such that compressors essentially identical but arranged for installation in different positions can readily be manufactured on the same tooling. If it is desired to install the second embodiment in a position corresponding to rotation clockwise 90from the position shown in FIG. (the side at the right of HO. 5 then becoming the bottom) the passage 210 and the outlet tube 212 will still be well above the oil level in the sump so that satisfactory operation in this position will ensue.

It will also be noted that although in the second embodiment the valve plates 177 are clamped under the cylinder heads 181 in the usual manner, the valve plate 77 of the first embodiment are relatively thin, of disc form, and secured only at their centers to the central reentrant boss 87 on the head 81 which also positions the outlet valve 78. Valve plates 77 are apertured in the normal manner, are of such stiffness that they remain seated during normal operation, but can flex in event of oil slugging and thereby act as supplemental oil-relief valving. The spacer 79 between the valve 78 and valve plate 77 prevents surface tension of the oil between the valve and valve plate from interfering with the action of the valve.

This Detailed Description of Preferred Forms of the [mention, and the accompanying drawings, have been furnished in compliance with the statutory requirement to set forth the best mode contemplated by the inventors of carrying out the invention. The prior portions consisting of the Abstract of the Disclosure and the Background of the Invention are furnished without prejudice in an effort to comply with administrative requirements of the Patent Office.

We claim:

1. In a refrigeration compressor comprising a pair of opposed axially aligned reciprocatory pistons, a crankshaft rotatable on an axis between the pistons and perpendicularly intersecting the common axis thereof, a Scotch yoke for actuating both pistons, a cross-slide in the yoke, and a crank throw on the crankshaft rotatably fitted in the slide, the novelty which comprises means for supporting and lubricating the crankshaft and connected parts including a housing structure having a bearing support at one end of the crankshaft, a low pressure lubricant chamber communicating with said end of the crankshaft, a rotatable male bearing portion of said crankshaft and havin an oil assage communicating with said chamber, and means or fee mg 011 to said chamber and then to said passage and for regulating the pressure therein, including a high pressure oil sump pressurized by the full output pressure of the compressor and a capillary tube having a uniform diameter which is small in proportion to its length connecting said sump to said chamber.

2. A compressor as defined in claim 1 wherein a portion of said chamber is formed by a recess in said male bearing portron.

3. A compressor as defined in claim 1 wherein the diameter of the male bearing portion exceeds the diameter of the orbit of the crank throw and a portion of said chamber is formed by a recess in said male bearing portion.

4. In a refrigeration compressor of the externally driven type, a body having front, central and rear sections, a shaft rotatably supported in the body and projecting from the front section, an inlet chamber closed by the front section, compression means in the central section, a high pressure outlet chamber closed by the rear section and having an oil sump therein, and means for lubricating operative components of the compressor including a low pressure oil chamber, pressure reducing oil feed means powered by pressure in the outlet chamber and connecting the sump to the low pressure chamber, and means for conducting oil from the low pressure chamber to the operative components.

5. A compressor as defined in claim 4 wherein said oil feed means comprises a restricted capillary tube connecting the sump to the low'pressure oil chamber.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 587,406 Dated June 28, 1971 Inventor(s) Edwin L. Gannaway and Robert M. Draper It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, line 11, after "reliable" delete -and--.

Col. 1, line 12, after "noise" insert and-.

Col. 2, line 43, after lubrioation", "to" should be of. Col. 3, line 32, "de-sign" should be --design--.

Col. 3, line 37, should be -5--.

Claim 1 C01. 4, line 21, after "portion" insert --secured to said throw and forming a journaled end portion-- Claim 1 C01. 4, line 28, after "chamber" insert --and in open communication with both.

Signed and sealed this L th day of January 1972.

(SEAL) At'test:

EDWARD M.FLETCHER, JR. ROBERT GOTTSCI-IALK Attesting Officer Acting Commissioner of Patents r q i FORM PO 1030 no 69) uscoMM-oc GUNS-P69 E "I U 5 GOVERNMENT PRINTING OFFICK |959 0-365-334 

